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41.
《Marine Policy》2014
Future fish demand-supply scenarios project that investment in aquaculture will be needed to ensure fish for food security in Solomon Islands. In 2010 a study of two peri-urban areas of Solomon Islands analysed the demand and potential for inland aquaculture, and the role of the introduced Mozambique tilapia (Oreochromis mossambicus) in household livelihoods and existing value chains. Of 178 households interviewed, marine reef fish were the preferred fish for consumption, although tinned fish was also common. At the study sites, Mozambique tilapia was accessible and contributed to food security, particularly for inland households. Sixty five percent of the people actively fished for tilapia at least monthly; 13% of these fished on almost a daily basis. Fish were consumed by men, women and children and sold by both men and women in local village markets. Mozambique tilapia is considered to perform poorly in aquaculture. While other species like Nile tilapia or milkfish (Chanos chanos) are being considered for aquaculture by the Solomon Islands Government, Mozambique tilapia is currently the only cost-effective and widely available alternative for farming fish for household food security. This study lends weight to the premise that peri-urban households that are cash poor are likely to benefit nutritionally from easier access to tilapia or other freshwater fish. 相似文献
42.
Interest in the role that cities can play in climate change as sites of transformation has increased but research has been limited in its practical applications and there has been limited consideration of how policies and technologies play out. These challenges necessitate a re-thinking of existing notions of urban governance in order to account for the practices that emerge from governments and a plethora of other actors in the context of uncertainty. We understand these practices to constitute adaptive governance, underpinned by social learning guiding the actions of the multiplicity of actors. The aim here is to unpack how social learning for adaptive governance requires attention to competing understandings of risk and identity, and the multiplicity of mechanisms in which change occurs or is blocked in urban climate governance. We adopt a novel lens of ‘environmentalities’ which allows us to assess the historical and institutional context and power relations in the informal settlements of Maputo, Mozambique. Our findings highlight how environmental identities around urban adaptation to climate change are constituted in the social and physical divisions between the formal and informal settlements, whilst existing knowledge models prioritise dominant economic and political interests and lead to the construction of new environmental subjects. While the findings of this study are contextually distinct, the generalizable lessons are that governance of urban adaptation occurs and is solidified within a complex multiplicity of socio-ecological relations. 相似文献
43.
A magnitude 7 earthquake occurred in southwest Mozambique in February 2006, triggering extensive liquefaction around the fault rupture. Samples were recovered from the liquefied soils for laboratory testing to calibrate a numerical model for the assessment of liquefaction susceptibility. Laboratory tests and simulations confirm that the alluvial sands from the area affected by the earthquake have a very high susceptibility to liquefaction, although this depends strongly on the in situ density, which is likely to be low since the soils are deposited in a major flood plain. Since many areas of Mozambique, including parts of the major coastal cities, are on similarly loose and saturated deposits, there could be a significant liquefaction hazard in future earthquakes. 相似文献
44.
Joachim Jacobs 《Gondwana Research》1999,2(3):473
New geochronological data indicate that central Dronning Maud Land in East Antarctica underwent polyphase Neoproterozoic/Lower Palaeozoic metamorphism that can be correlated with the final amalgamation of E- and W-Gondwana. Central Dronning Maud Land most probably represents part of the southern continuation of the Mozambique Belt into E-Antarctica. The Neoproterozoic/Lower Palaeozoic metamorphism is preceded by a period of anorogenic anorthosite-charnockite magmatism at ca. 600 Ma. Polyphase metamorphism is recorded from ca. 580 to 515 Ma. Voluminous syntectonic magmatism has been documented at ca. 530 Ma, which is probably the most voluminous Neoproterozoic/Lower Palaeozoic syntectonic magmatism so far recorded in E-Antarctica. The Neoproterozoic/Lower Palaeozoic structural evolution evolved in an overall sinistral transpressional setting, and thus can be correlated with the broad tectonic setting of the Mozambique Belt in Africa. 相似文献
45.
《African Journal of Marine Science》2013,35(3):573-580
Shark bite injuries on reef manta rays Manta alfredi off the coast of Inhambane, Mozambique, were examined over a three-year period (2003–2006). The frequency and seasonality of attacks, the rate of wound healing, and the possible identities of attackers were explored. This study presents the first examination of bite wounds on manta rays in the wild and the role sharks may play in the natural mortality of this species. The reported incidence of shark-inflicted injuries is high with over three-quarters of the sampled population affected. In total, 571 bite injuries were observed on 283 identified individuals. The number of bite injuries varied from one to seven, with a mean of 1.54 bite wounds. There was no significant difference in the frequency of bite injuries in male and female rays. The majority (96%) of the observed bite wounds were healed. Fresh wounds occurred throughout the year, with no obvious seasonality. The bull shark Carcharhinus leucas and tiger shark Galeocerdo cuvier are suggested as the primary mediators of attacks, although up to 11 other shark species are listed as potential attackers. The majority of the bite marks (96%) occurred to the most posterior region of the body, specifically the posterior edges of the pectoral and pelvic fins, with many injuries likely having a negative impact on the reproductive abilities and fitness of the rays. 相似文献
46.
《African Journal of Marine Science》2013,35(2):269-281
Fish were surveyed by visual census on offshore reefs in Mozambique and eastern South Africa to compare (a) fully-protected ‘sanctuary’ areas, (b) ‘partly protected’ areas where recreational diving and limited fishing are permitted, and (c) ‘open’ unprotected areas. Community composition differed between coral-dominated reefs and those covered mainly by algae and sponges, but not among treatments. Larger size classes were significantly diminished in unprotected areas compared to protected and sanctuary zones. Within coral-dominated reefs, abundances of indicator taxa showed three patterns: (1) greatest abundance in sanctuaries, intermediate in partly protected and least in open areas; (2) greatest abundance in sanctuaries but equal diminishment in partly protected and open areas; and (3) greater depletion in partly protected than either sanctuary or open areas. We conclude that partial protection does not effectively conserve reef fish, and there are indications that partly protected areas concentrate fishing effort on ‘pelagic’ gamefish. Sanctioned shore-angling and offshore ‘gamefishing’, illegal fishing and diver disturbance may collectively undermine the efficacy of partially protected areas. The depletion of reef fish species inside protected areas and reconsideration of the classification of pelagic gamefish require managerial attention. Partly protected areas in Mozambique need to be supplemented with no-take zones. 相似文献
47.
We investigate Pacific Decadal Oscillation (PDO) signals recorded by two bimonthly resolved coral δ18O series from La Réunion and Ifaty (West Madagascar), Indian Ocean from 1882 to 1993. To isolate the main PDO frequencies,
we apply a band pass filter to the time series passing only periodicities from 16 to 28 years. We investigate the covariance
patterns of the coral time series with sea surface temperature (SST) and sea level pressure (SLP) of the Indian and Pacific
Oceans. In addition, the empirical orthogonal functions of the filtered SST and SLP fields (single and coupled) are related
to the filtered coral times series. The covariance maps show the typical PDO pattern for SST and SLP, confirming the coupling
between the Indian and Pacific Oceans. Both corals show the strongest signal in boreal summer. The La Réunion (Ifaty) coral
better records SST (SLP) than SLP (SST) pattern variability. We suggest that the filtered La Réunion coral δ18O represents δ18O of seawater that varies with the South Equatorial Current, which, in turn, is linked with the SST PDO. The filtered Ifaty
coral δ18O represents SST and is remotely linked with the SLP PDO variability. A combined coral record of the Ifaty and La Réunion
boreal summer δ18O series explains about 64% of the variance of the coupled SST/SLP PDO time series.
AGU OS06 special issue “Ocean’s role in climate change—a paleo perspective”. 相似文献
48.
Similarities in the marine fauna found off the coasts of southern Madagascar and KwaZulu-Natal Province (KZN), South Africa, led to the development of the ‘suitcase project,’ with the aim of establishing whether eddies that form off southern Madagascar may package and transport biological material across the Mozambique Channel, facilitating connectivity and gene flow. Meroplankton (larval stages of fishes and benthic invertebrates) were collected on the Madagascan shelf and along a transect through a cyclonic eddy in the Mozambique Channel. The samples were analysed using microscopy and DNA barcoding, seeking to identify species known to be common to both the southeast coast of Madagascar and the east coast of South Africa and thereby to reveal potential indicators of connectivity between these regions. The greatest zooplankton biovolume in the upper 200 m occurred on the shelf, followed by in the western part of the eddy and in the region outside the eddy to the west, and was lowest in the region outside the eddy to the east. The meroplankton were dominated by taxa of coastal origin and these were also most abundant on the shelf and in the western part of the eddy, with the lowest abundances in the region outside the eddy to the east. The findings show greater zooplankton biovolumes and larval abundances and the presence of reef-associated larval assemblages on the Madagascan shelf and along the transect through the cyclonic eddy, providing support for the suitcase hypothesis that planktonic organisms are entrained within eddies as they propagate south-westwards of the Madagascan shelf. 相似文献
49.
将莫桑比克金矿划分为条带状含铁石英岩型、石英脉型、石英网脉型和砂金型4个类型,并分别论述了其分布和地质特征,讨论了金矿的找矿问题。 相似文献
50.